3.5 inch tft lcd arduino uno free sample
Displays are one of the best ways to provide feedback to users of a particular device or project and often the bigger the display, the better. For today’s tutorial, we will look on how to use the relatively big, low cost, ILI9481 based, 3.5″ Color TFT display with Arduino.
This 3.5″ color TFT display as mentioned above, is based on the ILI9481 TFT display driver. The module offers a resolution of 480×320 pixels and comes with an SD card slot through which an SD card loaded with graphics and UI can be attached to the display. The module is also pre-soldered with pins for easy mount (like a shield) on either of the Arduino Mega and Uno, which is nice since there are not many big TFT displays that work with the Arduino Uno.
The module is compatible with either of the Arduino Uno or the Arduino Mega, so feel free to choose between them or test with both. As usual, these components can be bought via the links attached to them.
One of the good things about this module is the ease with which it can be connected to either of the Arduino Mega or Uno. For this tutorial, we will use the Arduino Uno, since the module comes as a shield with pins soldered to match the Uno’s pinout. All we need to do is snap it onto the top of the Arduino Uno as shown in the image below, thus no wiring required.
This ease of using the module mentioned above is, however, one of the few downsides of the display. If we do not use the attached SD card slot, we will be left with 6 digital and one analog pin as the module use the majority of the Arduino pins. When we use the SD card part of the display, we will be left with just 2 digital and one analog pin which at times limits the kind of project in which we can use this display. This is one of the reasons while the compatibility of this display with the Arduino Mega is such a good news, as the “Mega” offers more digital and analog pins to work with, so when you need extra pins, and size is not an issue, use the Mega.
To easily write code to use this display, we will use the GFX and TFT LCD libraries from “Adafruit” which can be downloaded here. With the library installed we can easily navigate through the examples that come with it and upload them to our setup to see the display in action. By studying these examples, one could easily learn how to use this display. However, I have compiled some of the most important functions for the display of text and graphics into an Arduino sketch for the sake of this tutorial. The complete sketch is attached in a zip file under the download section of this tutorial.
As usual, we will do a quick run through of the code and we start by including the libraries which we will use for the project, in this case, the Adafruit GFX and TFT LCD libraries.
With this done, the Void Setup() function is next. We start the function by issuing atft.reset() command to reset the LCD to default configurations. Next, we specify the type of the LCD we are using via the LCD.begin function and set the rotation of the TFT as desired. We proceed to fill the screen with different colors and display different kind of text using diverse color (via the tft.SetTextColor() function) and font size (via the tft.setTextSize() function).
Spice up your Arduino project with a beautiful large touchscreen display shield with built in microSD card connection. This TFT display is big (3.5" diagonal) bright (6 white-LED backlight) and colorful (18-bit 262,000 different shades)! 320x480 pixels with individual pixel control. As a bonus, this display has a optional resistive touch panel with controller XPT2046 attached by default and a optional capacitive touch panel with controller FT6236 attached by default, so you can detect finger presses anywhere on the screen and doesn"t require pressing down on the screen with a stylus and has nice glossy glass cover.
The pin32 (SDO) of 3.5 display module is also used by touch panel or SD card SPI interface, so we must cut off this pin to avoid conflict with the touch panel or SD card.
The shield is fully assembled, tested and ready to go. No wiring, no soldering! Simply plug it in and load up our library - you"ll have it running in under 10 minutes! Works best with any classic Arduino (Due/Mega 2560).
Of course, we wouldn"t just leave you with a datasheet and a "good luck!" - we"ve written a full open source graphics library at the bottom of this page that can draw pixels, lines, rectangles, circles and text. We also have a touch screen library that detects x,y and z (pressure) and example code to demonstrate all of it. The code is written for Arduino but can be easily ported to your favorite microcontroller!
If you"ve had a lot of Arduino DUEs go through your hands (or if you are just unlucky), chances are you’ve come across at least one that does not start-up properly.The symptom is simple: you power up the Arduino but it doesn’t appear to “boot”. Your code simply doesn"t start running.You might have noticed that resetting the board (by pressing the reset button) causes the board to start-up normally.The fix is simple,here is the solution.
In this Arduino touch screen tutorial we will learn how to use TFT LCD Touch Screen with Arduino. You can watch the following video or read the written tutorial below.
For this tutorial I composed three examples. The first example is distance measurement using ultrasonic sensor. The output from the sensor, or the distance is printed on the screen and using the touch screen we can select the units, either centimeters or inches.
As an example I am using a 3.2” TFT Touch Screen in a combination with a TFT LCD Arduino Mega Shield. We need a shield because the TFT Touch screen works at 3.3V and the Arduino Mega outputs are 5 V. For the first example I have the HC-SR04 ultrasonic sensor, then for the second example an RGB LED with three resistors and a push button for the game example. Also I had to make a custom made pin header like this, by soldering pin headers and bend on of them so I could insert them in between the Arduino Board and the TFT Shield.
Here’s the circuit schematic. We will use the GND pin, the digital pins from 8 to 13, as well as the pin number 14. As the 5V pins are already used by the TFT Screen I will use the pin number 13 as VCC, by setting it right away high in the setup section of code.
I will use the UTFT and URTouch libraries made by Henning Karlsen. Here I would like to say thanks to him for the incredible work he has done. The libraries enable really easy use of the TFT Screens, and they work with many different TFT screens sizes, shields and controllers. You can download these libraries from his website, RinkyDinkElectronics.com and also find a lot of demo examples and detailed documentation of how to use them.
After we include the libraries we need to create UTFT and URTouch objects. The parameters of these objects depends on the model of the TFT Screen and Shield and these details can be also found in the documentation of the libraries.
So now I will explain how we can make the home screen of the program. With the setBackColor() function we need to set the background color of the text, black one in our case. Then we need to set the color to white, set the big font and using the print() function, we will print the string “Arduino TFT Tutorial” at the center of the screen and 10 pixels down the Y – Axis of the screen. Next we will set the color to red and draw the red line below the text. After that we need to set the color back to white, and print the two other strings, “by HowToMechatronics.com” using the small font and “Select Example” using the big font.
Here’s that function which uses the ultrasonic sensor to calculate the distance and print the values with SevenSegNum font in green color, either in centimeters or inches. If you need more details how the ultrasonic sensor works you can check my particular tutorialfor that. Back in the loop section we can see what happens when we press the select unit buttons as well as the back button.
In order the code to work and compile you will have to include an addition “.c” file in the same directory with the Arduino sketch. This file is for the third game example and it’s a bitmap of the bird. For more details how this part of the code work you can check my particular tutorial. Here you can download that file:
This small 3.5-inch touch screen module is designed specially for Arduino UNO. This is ideal for DIY anywhere, anytime, and does not require any separate power source or case to hold it. The screen also comes with a stylus to interact with the small screen.
Note: There is a film on the LCD, if there is scratch on the film when you receive the item, pls try to remove the film with your finger nail from the corner of the LCD, thanks.
The desire to develop a simulated analog display went hand in hand with the desire to have a test bench, that is, a compact device including an Arduino, a display and connectors to plug in all sorts of external sensors.
Here I discuss the construction of a ‘test bench’ powered by an Arduino Nano, and equipped with a versatile 3.5 inch 320×480 pixel color TFT display. In this example the test bench is used to measure ambient room temperature with a Dallas DS18B20 sensor while relative humidity is simultaneously measured with a DHT11 sensor. The temperature is displayed numeriaclly and in a simulated analog fashion while the relative humidity is displayed only digitally. Construction of the bench is such that four digital pins on the Nano remain available for data sensing or for output. In addition, the A5 pin on the Nano is available for analogous sensing.
In previous papers I described the construction and wiring of a board powered by an Arduino Nano and equipped with a 3.5 inch 320×480 color TFT display for visual output of readings of scores of Dallas DS18B20 temperature sensors and DHT11 relative humidity sensors. One prototype and two ‘production’ versions of these devices were constructed. After commission they started to provide valuable data concerning the environmental situation inside and outside my home.
However successful, these devices were built to suit specific purposes, that is, monitoring input-output temperatures in floor heating loops and measuring temperatures of photovoltaic energy inverters in the attic. Their application is very satisfactory. Although the sensors of these devices can be unplugged and the devices used for test bench purposes, the unplugging, replugging and reprogramming appear to be quite cumbersome. It became desirable to construct a general purpose test bench device. This device should be fitted with a TFT display with sufficient pixel resolution. The luxury of having a TFT display available is partly offset because these displays ‘consume’ the majority of the available pins of an Arduino device. Nevertheless several pins remain available for input- or output purposes. As a TFT shield completely covers all pin headers on an Arduino Uno board these free pins should be made easily accessible in some way
A characteristic of the human brain is that we often find gauges and analog readings more pleasant and easier to interpret than readings on digital displays. Why not simulate an analog display on our Arduino? A matter of nostalgia, perhaps. Let’s construct an Arduino test bench with exposed free pins and with a simulated analog display!
The display (figure 1) is a combined 3.5 inch TFT display-memory card reader shield with the typical pin arrangement that nicely fits the female pin headers of an Arduino Uno microcontroller board. Of the 28 pins on the display’s pin headers, 16 need to be wired to the Arduino: the 5V, 3V3, GND pins and the pins marked ‘LCD_nn’. Because the shield requires specific pins on the Arduino to function properly, only a few pins on the Arduino remain free for experimentation purposes: pin A5 and pins D10 through D13.
As I favor the use of an Arduino Nano because of its small footprint and economy, and also because a TFT shield by design renders free pins of an Arduino Uno hardly accessible, I needed to create pin-to-pin wiring between the display and the Nano. While this can be achieved by simple soldering there is a more elegant way of connecting display and Nano: the pin-and-socket plugin approach.
Here, I used a 80×120 mm soldering board on which I soldered two rows of female pin headers together forming a socket that receives the display shield’s pin headers. This socket construction is neat and it enables quick replacement of a display with another one. A small challenge here was that the pin headers J2, J3 and J4 on the TFT shield (visible in figure 1) seamlessly match the hole pattern in the soldering board while pin header J1 misaligns with the soldering board’s holes. This problem was solved by milling a rectangular cut in the soldering board that exactly matched the position and dimensions of the J1 pin header on the TFT display. The female ‘socket-J1’ pin header on the soldering board was positioned on the board above the cutout, and glued to four braces: ‘support’ female pin headers soldered to the board, flanking the cutout.
Once the positions of the ‘socket’ female pin headers on the soldering board had been figured out, those accepting J2, J3 and J4 soldered into their final position and the J1 socket glued in place, the wiring could be installed. Figure 2 shows the wiring scheme. In order to free pins on the Nano the SD slot functionality on the TFT shield was not used.
figure 2. Schematic wiring of the components of the test bench. All parts seen from the back of the soldering board. 16 pins of the TFT display shield need to be connected with pins on the Nano. The SD card slot is not used.
figure 4. Actual wiring with the actual positioning of the components of the test bench. The front contains the Nano, the TFT screen, the 5V/GND connectors (painted red and black, respectively) and the data pin header (painted white for convenience). Labels were glued on the board.
figure 5. Board attached with two nuts onto the lid of a tape cassette box. A spacer keeps the back of the board a few millimeters away from the plastic lid. This protects the wiring from mechanical damage. Tape cassette box boxes can be applied as cheap and handy stands for Arduino projects; they are made of extruded acrylic and can be worked on with tools – carefully.
Once the test bench was ready I had a versatile test device at hand to perform Arduino experiments. In front of to the test bench a breadboard was placed that held a Dallas DS18B20 temperature sensor and a DHT11 temperature / relative humidity sensor. Temperature sensing with a Dallas DS18B20 is more accurate than with a DHT11.
As the analog meter is simulated in software I looked around and found at Instructables.com in the Arduino section a very nice contribution by Bodmer, named “Arduino sketch for a retro analogue meter graphic on a modern TFT display”. The core of Bodmer’s sketch forms a backbone display subroutine of the sketch that powers the TFT.
I successfully exchanged the 3.5 inch display with a 3.95 inch 320×480 color TFT display (featuring a ILI9488 controller) and with a 2.8 inch 240×320 color TFT display (ILI9341). These displays have two features in common. First, their pin header layouts are the same as that of the 3.5 inch display and second, they contain an ILI controller chip that is supported by David Prentice’s mcufriend_kbv library (available at the Arduino forum). The controller in the present 3.5′ TFT display is an ILI9481.
The goals of the present project were successfully achieved: constructing a test bench with an Arduino Nano powered ‘engine’ with a small footprint, displaying the measured values of several sensors in a simulated analog fashion on a color TFT display. The test bench is used to test sensors in various rooms, let’s say a hot water pipe in the attic whose temperature I want to monitor, or simply the air temperature in the shed. In these ‘remote’ locations the test bench is powered by a USB power bank. The analogous readings are pleasant for the eye.
In this article, you will learn how to use TFT LCDs by Arduino boards. From basic commands to professional designs and technics are all explained here.
There are several components to achieve this. LEDs, 7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.
TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.
There are several components to achieve this. LEDs, 7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.
TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.
After choosing the right display, It’s time to choose the right controller. If you want to display characters, tests, numbers and static images and the speed of display is not important, the Atmega328 Arduino boards (such as Arduino UNO) are a proper choice. If the size of your code is big, The UNO board may not be enough. You can use Arduino Mega2560 instead. And if you want to show high resolution images and motions with high speed, you should use the ARM core Arduino boards such as Arduino DUE.
In electronics/computer hardware a display driver is usually a semiconductor integrated circuit (but may alternatively comprise a state machine made of discrete logic and other components) which provides an interface function between a microprocessor, microcontroller, ASIC or general-purpose peripheral interface and a particular type of display device, e.g. LCD, LED, OLED, ePaper, CRT, Vacuum fluorescent or Nixie.
The LCDs manufacturers use different drivers in their products. Some of them are more popular and some of them are very unknown. To run your display easily, you should use Arduino LCDs libraries and add them to your code. Otherwise running the display may be very difficult. There are many free libraries you can find on the internet but the important point about the libraries is their compatibility with the LCD’s driver. The driver of your LCD must be known by your library. In this article, we use the Adafruit GFX library and MCUFRIEND KBV library and example codes. You can download them from the following links.
You must add the library and then upload the code. If it is the first time you run an Arduino board, don’t worry. Just follow these steps:Go to www.arduino.cc/en/Main/Software and download the software of your OS. Install the IDE software as instructed.
First you should convert your image to hex code. Download the software from the following link. if you don’t want to change the settings of the software, you must invert the color of the image and make the image horizontally mirrored and rotate it 90 degrees counterclockwise. Now add it to the software and convert it. Open the exported file and copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are sizes of image. you can change the color of the image in the last input.
Upload your image and download the converted file that the UTFT libraries can process. Now copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are size of the image.
In this template, We converted a .jpg image to .c file and added to the code, wrote a string and used the fade code to display. Then we used scroll code to move the screen left. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We used sin(); and cos(); functions to draw Arcs with our desired thickness and displayed number by text printing function. Then we converted an image to hex code and added them to the code and displayed the image by bitmap function. Then we used draw lines function to change the style of the image. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We added a converted image to code and then used two black and white arcs to create the pointer of volumes. Download the .h file and add it to the folder of the Arduino sketch.
In this template, We added a converted image and use the arc and print function to create this gauge. Download the .h file and add it to folder of the Arduino sketch.
while (a < b) { Serial.println(a); j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 255, 255)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)
while (b < a) { j = 80 * (sin(PI * a / 2000)); i = 80 * (cos(PI * a / 2000)); j2 = 50 * (sin(PI * a / 2000)); i2 = 50 * (cos(PI * a / 2000)); tft.drawLine(i2 + 235, j2 + 169, i + 235, j + 169, tft.color565(0, 0, 0)); tft.fillRect(200, 153, 75, 33, 0x0000); tft.setTextSize(3); tft.setTextColor(0xffff); if ((a/20)>99)
In this template, We display simple images one after each other very fast by bitmap function. So you can make your animation by this trick. Download the .h file and add it to folder of the Arduino sketch.
In this template, We just display some images by RGBbitmap and bitmap functions. Just make a code for touchscreen and use this template. Download the .h file and add it to folder of the Arduino sketch.
New functions have been added to draw smooth (antialiased) arcs, circles, and rounded rectangle outlines. New sketches are provided in the "Smooth Graphics" examples folder. Arcs can be drawn with or without anti-aliasing (which will then render faster). The arc ends can be straight or rounded. The arc drawing algorithm uses an optimised fixed point sqrt() function to improve performance on processors that do not have a hardware Floating Point Unit (e.g. RP2040). Here are two demo images, on the left smooth (anti-aliased) arcs with rounded ends, the image to the right is the same resolution (grabbed from the same 240x240 TFT) with the smoothing diasbled (no anti-aliasing):
An excellent new compatible library is available which can render TrueType fonts on a TFT screen (or into a sprite). This has been developed by takkaO, I have created a branch with some bug fixes here. The library provides access to compact font files, with fully scaleable anti-aliased glyphs. Left, middle and right justified text can also be printed to the screen. I have added TFT_eSPI specific examples to the OpenFontRender library and tested on RP2040 and ESP32 processors, the ESP8266 does not have sufficient RAM due to the glyph render complexity. Here is a demo screen where a single 12kbyte font file binary was used to render fully anti-aliased glyphs of gradually increasing size on a 320x480 TFT screen:
Smooth fonts can now be rendered direct to the TFT with very little flicker for quickly changing values. This is achieved by a line-by-line and block-by-block update of the glyph area without drawing pixels twice. This is a "breaking" change for some sketches because a new true/false parameter is needed to render the background. The default is false if the parameter is missing, Examples:
Frank Boesing has created an extension library for TFT_eSPI that allows a large range of ready-built fonts to be used. Frank"s library (adapted to permit rendering in sprites as well as TFT) can be downloaded here. More than 3300 additional Fonts are available here. The TFT_eSPI_ext library contains examples that demonstrate the use of the fonts.
Users of PowerPoint experienced with running macros may be interested in the pptm sketch generator here, this converts graphics and tables drawn in PowerPoint slides into an Arduino sketch that renders the graphics on a 480x320 TFT. This is based on VB macros created by Kris Kasprzak here.
An Arduino IDE compatible graphics and fonts library for 32 bit processors. The library is targeted at 32 bit processors, it has been performance optimised for RP2040, STM32, ESP8266 and ESP32 types, other processors may be used but will use the slower generic Arduino interface calls. The library can be loaded using the Arduino IDE"s Library Manager. Direct Memory Access (DMA) can be used with the ESP32, RP2040 and STM32 processors with SPI interface displays to improve rendering performance. DMA with a parallel interface (8 and 16 bit parallel) is only supported with the RP2040.
For other processors only SPI interface displays are supported and the slower Arduino SPI library functions are used by the library. Higher clock speed processors such as used for the Teensy 3.x and 4.x boards will still provide a very good performance with the generic Arduino SPI functions.
"Four wire" SPI and 8 bit parallel interfaces are supported. Due to lack of GPIO pins the 8 bit parallel interface is NOT supported on the ESP8266. 8 bit parallel interface TFTs (e.g. UNO format mcufriend shields) can used with the STM32 Nucleo 64/144 range or the UNO format ESP32 (see below for ESP32).
The library supports some TFT displays designed for the Raspberry Pi (RPi) that are based on a ILI9486 or ST7796 driver chip with a 480 x 320 pixel screen. The ILI9486 RPi display must be of the Waveshare design and use a 16 bit serial interface based on the 74HC04, 74HC4040 and 2 x 74HC4094 logic chips. Note that due to design variations between these displays not all RPi displays will work with this library, so purchasing a RPi display of these types solely for use with this library is NOT recommended.
A "good" RPi display is the MHS-4.0 inch Display-B type ST7796 which provides good performance. This has a dedicated controller and can be clocked at up to 80MHz with the ESP32 (125MHz with overclocked RP2040, 55MHz with STM32 and 40MHz with ESP8266). The MHS-3.5 inch RPi ILI9486 based display is also supported, however the MHS ILI9341 based display of the same type does NOT work with this library.
Some displays permit the internal TFT screen RAM to be read, a few of the examples use this feature. The TFT_Screen_Capture example allows full screens to be captured and sent to a PC, this is handy to create program documentation.
The library includes a "Sprite" class, this enables flicker free updates of complex graphics. Direct writes to the TFT with graphics functions are still available, so existing sketches do not need to be changed.
The "Animated_dial" example shows how dials can be created using a rotated Sprite for the needle. To run this example the TFT interface must support reading from the screen RAM (not all do). The dial rim and scale is a jpeg image, created using a paint program.
The XPT2046 touch screen controller is supported for SPI based displays only. The SPI bus for the touch controller is shared with the TFT and only an additional chip select line is needed. This support will eventually be deprecated when a suitable touch screen library is available.
The library supports SPI overlap on the ESP8266 so the TFT screen can share MOSI, MISO and SCLK pins with the program FLASH, this frees up GPIO pins for other uses. Only one SPI device can be connected to the FLASH pins and the chips select for the TFT must be on pin D3 (GPIO0).
Configuration of the library font selections, pins used to interface with the TFT and other features is made by editing the User_Setup.h file in the library folder, or by selecting your own configuration in the "User_Setup_Selet,h" file. Fonts and features can easily be enabled/disabled by commenting out lines.
It would be possible to compress the vlw font files but the rendering performance to a TFT is still good when storing the font file(s) in SPIFFS, LittleFS or FLASH arrays.
Anti-aliased fonts can also be drawn over a gradient background with a callback to fetch the background colour of each pixel. This pixel colour can be set by the gradient algorithm or by reading back the TFT screen memory (if reading the display is supported).
The common 8 bit "Mcufriend" shields are supported for the STM Nucleo 64/144 boards and ESP32 UNO style board. The STM32 "Blue/Black Pill" boards can also be used with 8 bit parallel displays.
Unfortunately the typical UNO/mcufriend TFT display board maps LCD_RD, LCD_CS and LCD_RST signals to the ESP32 analogue pins 35, 34 and 36 which are input only. To solve this I linked in the 3 spare pins IO15, IO33 and IO32 by adding wires to the bottom of the board as follows:
If you load a new copy of TFT_eSPI then it will overwrite your setups if they are kept within the TFT_eSPI folder. One way around this is to create a new folder in your Arduino library folder called "TFT_eSPI_Setups". You then place your custom setup.h files in there. After an upgrade simply edit the User_Setup_Select.h file to point to your custom setup file e.g.: